KAPAAU Hawaii (Reuters) - As Tropical Storm Iselle pushed past Hawaii late on Friday, thousands of residents raced to clear debris and restore power before another, more powerful hurricane threatened to drench the islands again within days.

Iselle had weakened into a tropical storm before reaching Hawaii and officials said it was blunted to some extent by the archipelago's mountainous Big Island, though high winds and heavy rain still lashed smaller islands in the chain.

Residents and officials worked to clean up fallen trees that had downed powerlines and turned their attention toward Saturday's primary election, which the storm had threatened to interrupt. The National Weather Service lifted its tropical storm warning for all of Hawaii late Friday.

"I think we've come through in great fashion," Governor Neil Abercrombie told an evening news conference, a nod to the fact that the storm's did much less damage than had been feared.

Officials, however, warned residents not to become complacent given the extent of the disruption and the uncertainty over the pathway of the bigger storm hurtling toward them.

"Next on tap is Hurricane Julio, which still is packing winds of about 100 mph (161 kph)," said National Weather Service meteorologist Mike Cantin. "Right now our guidance is indicating it's going to go north (of the state), but that can change and folks need to keep on guard."

State officials also gave the all-clear for a Democratic primary election to proceed as scheduled on Saturday. All but two polling stations on the hardest-hit east coast of the Big Island would be open, they said.

After Iselle passed, the U.S. Coast Guard said it had reopened all of its ports in the state except one on Molokai, which would be evaluated early on Saturday.

As Iselle passed over the Big Island with winds of up to 50 mph (80 kph) and pummeled eastern areas from Puna to Hilo with heavy rains, some 2,000 people had hunkered down in evacuation shelters across the state. Later in the day, that figure was reduced to about 900 people as many evacuees returned to their homes, said an American Red Cross spokeswoman.

At one point, 23,000 people were left without power on the Big Island and Maui, and some 15,000 customers on the Big Island headed into a second night without power.

"The air is thick with wood smoke since the power is still out," said Malia Baron, who was visiting the Volcano area of the Big Island. "It's been quite the adventure, but we're ready to head home to prep for the next storm."

Farmers on the largely rural Big Island were checking crops and fruit and macadamia nut trees for damage. Ka'u Coffee Mill, a grower, said it closed on Friday as farmers assessed damage to fields from flooding.

Other areas escaped relatively unscathed as the storm was split by the island's volcanic peaks.

"We took precautions to make sure things didn't blow away and to minimize damage if we in fact got high winds - but we didn't," said Bruce Corker, owner of Rancho Aloha coffee farm in Holualoa, in the Kona region.

There were no reports of major injuries from Iselle, a public relations boon to a state economy that depends heavily on tourism. Some 95,000 tourists were visiting at the time Iselle hit.

Emergency officials found the body of a man in his 50s or 60s in the ocean near Honolulu's Ala Moana Beach Park at about 5 p.m. local time, but it was not immediately clear whether his death was weather-related, the Honolulu Star-Advertiser newspaper reported.

'NOW THERE'S JULIO'

Julio, which was downgraded to a Category 2 storm on Friday, was churning toward Hawaii at about 16 mph (26 kph), carrying maximum sustained winds of 100 mph (155 kph), and was expected to affect the islands as early as Sunday.

It was 680 miles (1,095 km) east of Hilo and 870 miles (1,405 km) east of Honolulu, according to the National Weather Service.

"It's raining hard here, but I guess I can expect that the worst of Iselle is over. Now there's Julio to worry about," said Pepeekeo resident Rae Miyashiro, who experienced power outages overnight.

Forecasts showed Julio weakening still further as it nears Hawaii, likely tracking about 150 miles (240 km) north of the archipelago early on Sunday at the earliest, National Weather Service meteorologist Anthony Reynes said.

But even if the storm veers away from the Hawaiian Islands, forecasters said, it could still bring high winds and considerable amounts of rain.

"At the very least it will have a significant impact on surf on north- and east-facing shores - waves could be between 10 and 15 feet (3 to 4.5 metres) or even higher," Reynes said.

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